(a) Field of the Invention
The present invention relates to a portable sound reproducing system and method, and more particularly, to a portable sound reproducing system and a reproducing method thereof in which sound data, compressed using the Moving Picture Experts Group (MPEG) method and stored in a memory device, is converted into an audible format and output through headphones, speakers, etc.
(b) Description of the Related Art
Generally, data processed to be listened or viewed is stored in a memory medium then output through a reproduction device. The most common examples include analog data stored on magnetic tape which is output through a cassette player, and digital data stored on a compact disc which is output through a compact disc player.
Recent developments in digital technology has enabled memory media used in personal computers to undergo vast improvements. Namely, memory media used in PCs are becoming increasingly lightweight and compact, and providing the user with more capacity to store memory.
However, with the increase in required memory needed to run operating systems and application software, there is a limit to how efficiently memory media can be used. In an attempt to remedy this problem, a variety of methods have been devised to enable the efficient use of digital data. The MPEG standard is one of these methods which increases the storage capacity of memory media by compressing data stored therein.
Namely, by using the MPEG method of compressing data, data is compressed to roughly one-twelfth its original size without compromising sound or visual quality. After compresing data utilizing software or hardware made for this purpose, the data is then stored in a storage medium, then converted back into its original state using the MPEG method such that the data is placed in a form that can be heard or seen by the user. The MPEG method, therefore greatly increases data storage capacity.
With all the conventional sound reproduction systems, i.e., tape players and compact disc players, and PCs, etc. which are equipped with the capability to reproduce MPEG-compressed data, many disadvantages are encountered by the user.
In particular, in using cassette players, which reproduce data stored on magnetic tape, because the same amount of time is needed to store (record) data as it does to reproduce (play) the data, the storing process is time-consuming, and heat generated during the process acts to deteriorate the quality of the recording such that the quality of the sound reproduced is decreased. Moreover, because magnetic tape is easily worn, the repetitive playing of data stored on the cassette tape also acts to reduce sound quality.
Compact disc players and the discs used therein also have many problems. Namely, recording is not possible on compact discs. Further, because of the mechanical fragility of CD players, reproduction malfunctions occur when the players receive even slight outside shocks. Finally, CD players have a limited life span as the mechanical parts in the devices often break over time.
The storage media used in cassette and CD players also have the drawback of occupying much space. Also, users must take great care that the storage media are placed in an area that is not exposed to heat, direct sunlight, etc.
With regard to prior art devices such as PCs used to reproduce data stored using the MPEG method, as these devices are not portable, the location at which users can access the sound and images is limited to the location of the device. In addition, when using a PC to reproduce data compressed using the MPEG method, the cost of equipping the PC with software or hardware to enable this function is high. Also, because various types of sound data are stored on a plurality of storage media, the user must purchase many kinds of storage media and undergo complicated processes to reproduce the data stored therein.
Finally, in all of the above cases, users must physically go to retail stores to purchase storage media, causing inconvenience to the user.
The present invention has been made in an effort to solve the above problems. It is an object of the present invention to provide an MPEG portable sound reproducing system and a reproducing method thereof which reproduces sound data, compressed and stored on a memory chip using the MPEG method, into an audible format.
It is another object of the present invention to provide an MPEG portable sound reproducing system which, by storing data on a semiconductor storage medium, prevents heat from generating during recording as in the prior art cassette tape player, and avoids damage from exposure to heat as with conventional cassette tapes, compact discs, and other storage media.
It is still yet another object of the present invention to provide an MPEG portable sound reproducing system which enables connection to telecommunications networks and data vending machines such that various data can be downloaded, thereby enabling users to enjoy the benefits- speed, convenience, variety, etc.- of these systems.
It is still yet another object of the present invention to provide an MPEG portable sound reproducing system in which data downloaded via telecommunications networks and data vending machines as in the above is able to be accessed by and saved on a personal computer.
It is still yet another object of the present invention to provide an MPEG portable sound reproducing system which does not require separate storage media as with cassette players and compact disc players such that the device can be made to be lightweight and thin, and the need for physical storage space of the storage media is not needed.
To achieve the above objects, the present invention provides an MPEG portable sound reproducing system and a method for reproducing sound data compressed using the MPEG method. The inventive system includes power supply means for supplying operational power to the system, the power supply means being realized through a secondary battery; power processing means for rectifying power supplied from the power supply means to stable voltage and current; information display means for displaying numbers and combinations of letters related to operational states of the system; control means for controlling all operations of converting and reproducing sound data compressed using the MPEG method; data storage means for storing MPEG-compressed sound data in a designated address according to signals output from the control means; information selecting means for selecting general operations to reproduce, download, and apply selected sound data stored in the data storage means; sound reproducing means for converting sound data stored in the data storage means into a format audible to users according to signals output from the control means; and transmitting/receiving means for transmitting and receiving sound data and program data from external devices.
The inventive sound reproducing method includes the steps of initializing the system and detecting a state of a flash ROM when power is supplied to information selecting means; loading a main program from the flash ROM, if it is detected that the state of the flash ROM is normal, and completing booting of required software; and downloading and reproducing stored sound data, if the set up of the operational environment is completed, according to signals output from the information selecting means, a state of operational power, and whether connection is made to an external power supply and to external telecommunications systems, etc.